Dennis R Zook

Insider

First SEC filing: Sept. 29, 2003 · Latest: Sept. 29, 2003

On this page

Insider at Companies where this person is a reporting insider.
Insider transactions Every share this person bought or sold, from Form 4 filings.
Derivatives Options and other derivative holdings reported by this person.
Compensation Executive pay disclosed in company proxy statements.

Insider at

COST selling Oct. 25, 2017

Insider transactions

0 buys (P) 0 sells (S) Net: $0 + 78 non-open-market transactions below last 12 months, based on the transactions shown below

Price change vs current quote, split-adjusted for corporate actions since the filing — not benchmarked, not annualized, not size-weighted

78 other filings hidden

Date	Ticker	Code	Shares	Price	Value	Owned after	Δ own	A/D	vs now
Oct. 2, 2018	COST	F	8,627	$236.35	$2,038,991	10,053 Direct	-46.18%	Disposed	299.1% (price as of 2026-08-21)
Oct. 2, 2018	COST	A	18,680	—	—	18,680 Direct	—	Acquired	(price as of 2026-08-21)
Oct. 25, 2017	COST	S	5,000	$162.16	$810,800	13,265 Indirect	-27.37%	Disposed	481.7% (price as of 2026-08-21)
Oct. 24, 2017	COST	S	5,000	$161.92	$809,600	18,265 Indirect	-21.49%	Disposed	482.5% (price as of 2026-08-21)
Oct. 4, 2017	COST	J	10,537	—	—	23,265 Indirect	+82.79%	Acquired	(price as of 2026-08-21)
Oct. 4, 2017	COST	J	10,537	—	—	626 Direct	-94.39%	Disposed	(price as of 2026-08-21)
Oct. 2, 2017	COST	A	626	$165.89	$103,847	11,163 Direct	+5.94%	Acquired	468.6% (price as of 2026-08-21)
Oct. 2, 2017	COST	F	9,659	$165.89	$1,602,332	10,537 Direct	-47.83%	Disposed	468.6% (price as of 2026-08-21)
Oct. 2, 2017	COST	A	19,570	—	—	20,196 Direct	+3126.20%	Acquired	(price as of 2026-08-21)
May 24, 2017	COST	A	0	—	—	0 Direct	—	Acquired	(price as of 2026-08-21)
May 24, 2017	COST	A	626	$173.01	$108,304	626 Direct	—	Acquired	445.2% (price as of 2026-08-21)
Nov. 15, 2016	COST	S	10,000	—	—	19,694 Direct	-33.68%	Disposed	(price as of 2026-08-21)
Oct. 22, 2016	COST	F	3,207	$148.97	$477,747	29,694 Direct	-9.75%	Disposed	533.2% (price as of 2026-08-21)
Oct. 22, 2016	COST	F	3,046	$148.97	$453,763	32,901 Direct	-8.47%	Disposed	533.2% (price as of 2026-08-21)
Oct. 22, 2016	COST	F	2,284	$148.97	$340,247	35,947 Direct	-5.97%	Disposed	533.2% (price as of 2026-08-21)
Oct. 22, 2016	COST	F	1,950	$148.97	$290,492	38,231 Direct	-4.85%	Disposed	533.2% (price as of 2026-08-21)
Oct. 22, 2016	COST	F	975	$148.97	$145,246	40,181 Direct	-2.37%	Disposed	533.2% (price as of 2026-08-21)
Oct. 5, 2016	COST	F	5,442	$149.98	$816,191	41,156 Direct	-11.68%	Disposed	528.9% (price as of 2026-08-21)
Oct. 5, 2016	COST	A	18,440	—	—	46,598 Direct	+65.49%	Acquired	(price as of 2026-08-21)
March 14, 2016	COST	S	4,075	$152.96	$623,312	28,158 Direct	-12.64%	Disposed	516.7% (price as of 2026-08-21)
Oct. 22, 2015	COST	F	975	$158.15	$154,196	35,710 Direct	-2.66%	Disposed	496.4% (price as of 2026-08-21)
Oct. 22, 2015	COST	F	975	$158.15	$154,196	34,735 Direct	-2.73%	Disposed	496.4% (price as of 2026-08-21)
Oct. 22, 2015	COST	F	977	$158.15	$154,513	33,758 Direct	-2.81%	Disposed	496.4% (price as of 2026-08-21)
Oct. 22, 2015	COST	F	763	$158.15	$120,668	32,995 Direct	-2.26%	Disposed	496.4% (price as of 2026-08-21)
Oct. 22, 2015	COST	F	762	$158.15	$120,510	32,233 Direct	-2.31%	Disposed	496.4% (price as of 2026-08-21)
Oct. 12, 2015	COST	S	9,000	$153.96	$1,385,640	36,685 Direct	-19.70%	Disposed	512.7% (price as of 2026-08-21)
Sept. 24, 2015	COST	F	6,613	$144.87	$958,025	46,585 Direct	-12.43%	Disposed	551.1% (price as of 2026-08-21)
Sept. 24, 2015	COST	A	21,000	—	—	53,198 Direct	+65.22%	Acquired	(price as of 2026-08-21)
Feb. 27, 2015	COST	A	1,599	$146.96	$234,989	31,298 Direct	+5.38%	Acquired	541.8% (price as of 2026-08-21)
Jan. 12, 2015	COST	S	8,000	$142.54	$1,140,320	29,699 Direct	-21.22%	Disposed	561.7% (price as of 2026-08-21)
Oct. 22, 2014	COST	F	936	$130.54	$122,185	41,239 Direct	-2.22%	Disposed	622.6% (price as of 2026-08-21)
Oct. 22, 2014	COST	F	935	$130.54	$122,055	40,304 Direct	-2.27%	Disposed	622.6% (price as of 2026-08-21)
Oct. 22, 2014	COST	F	937	$130.54	$122,316	39,367 Direct	-2.32%	Disposed	622.6% (price as of 2026-08-21)
Oct. 22, 2014	COST	F	937	$130.54	$122,316	38,430 Direct	-2.38%	Disposed	622.6% (price as of 2026-08-21)
Oct. 22, 2014	COST	F	731	$130.54	$95,425	37,699 Direct	-1.90%	Disposed	622.6% (price as of 2026-08-21)
Oct. 13, 2014	COST	S	7,000	$128.10	$896,700	42,175 Direct	-14.23%	Disposed	636.3% (price as of 2026-08-21)
Sept. 26, 2014	COST	F	6,157	$125.54	$772,950	49,175 Direct	-11.13%	Disposed	651.4% (price as of 2026-08-21)
Sept. 26, 2014	COST	A	21,000	—	—	55,332 Direct	+61.17%	Acquired	(price as of 2026-08-21)
Oct. 22, 2013	COST	F	937	$117.81	$110,388	32,425 Direct	-2.81%	Disposed	700.7% (price as of 2026-08-21)
Oct. 22, 2013	COST	F	938	$117.81	$110,506	33,362 Direct	-2.73%	Disposed	700.7% (price as of 2026-08-21)
Oct. 22, 2013	COST	F	938	$117.81	$110,506	34,300 Direct	-2.66%	Disposed	700.7% (price as of 2026-08-21)
Oct. 22, 2013	COST	F	936	$117.81	$110,270	35,238 Direct	-2.59%	Disposed	700.7% (price as of 2026-08-21)
Oct. 22, 2013	COST	F	936	$117.81	$110,270	36,174 Direct	-2.52%	Disposed	700.7% (price as of 2026-08-21)
Oct. 16, 2013	COST	S	10,000	$116.37	$1,163,700	37,110 Direct	-21.23%	Disposed	710.6% (price as of 2026-08-21)
Sept. 20, 2013	COST	A	1,907	$117.94	$224,912	49,017 Direct	+4.05%	Acquired	699.8% (price as of 2026-08-21)
Sept. 20, 2013	COST	F	8,136	$117.94	$959,560	47,110 Direct	-14.73%	Disposed	699.8% (price as of 2026-08-21)
Sept. 20, 2013	COST	A	25,000	—	—	55,246 Direct	+82.66%	Acquired	(price as of 2026-08-21)
April 3, 2013	COST	S	4,000	$106.50	$426,000	30,246 Direct	-11.68%	Disposed	785.7% (price as of 2026-08-21)
Dec. 12, 2012	COST	A	1,270	$98.31	$124,854	34,246 Direct	+3.85%	Acquired	859.5% (price as of 2026-08-21)
Oct. 26, 2012	COST	S	11,000	$96.29	$1,059,190	32,976 Direct	-25.01%	Disposed	879.6% (price as of 2026-08-21)
Oct. 22, 2012	COST	F	779	$95.00	$74,005	43,976 Direct	-1.74%	Disposed	892.9% (price as of 2026-08-21)
Oct. 22, 2012	COST	F	779	$95.00	$74,005	44,755 Direct	-1.71%	Disposed	892.9% (price as of 2026-08-21)
Oct. 22, 2012	COST	F	779	$95.00	$74,005	45,534 Direct	-1.68%	Disposed	892.9% (price as of 2026-08-21)
Oct. 22, 2012	COST	F	779	$95.00	$74,005	46,313 Direct	-1.65%	Disposed	892.9% (price as of 2026-08-21)
Oct. 17, 2012	COST	F	2,289	$96.78	$221,529	47,092 Direct	-4.64%	Disposed	874.6% (price as of 2026-08-21)
Sept. 26, 2012	COST	F	6,802	$101.00	$687,002	49,381 Direct	-12.11%	Disposed	833.9% (price as of 2026-08-21)
Sept. 26, 2012	COST	A	25,000	—	—	56,183 Direct	+80.17%	Acquired	(price as of 2026-08-21)
March 12, 2012	COST	S	7,900	—	—	31,183 Direct	-20.21%	Disposed	(price as of 2026-08-21)
Oct. 26, 2011	COST	S	13,802	—	—	39,083 Direct	-26.10%	Disposed	(price as of 2026-08-21)
Oct. 26, 2011	COST	S	5,000	$83.41	$417,050	52,885 Direct	-8.64%	Disposed	1030.9% (price as of 2026-08-21)
Oct. 26, 2011	COST	S	5,000	$83.41	$417,050	52,885 Direct	-8.64%	Disposed	1030.9% (price as of 2026-08-21)
Oct. 22, 2011	COST	F	4,668	$85.30	$398,180	57,885 Direct	-7.46%	Disposed	1005.8% (price as of 2026-08-21)
Oct. 22, 2011	COST	F	3,891	$85.30	$331,902	62,553 Direct	-5.86%	Disposed	1005.8% (price as of 2026-08-21)
Oct. 22, 2011	COST	F	3,113	$85.30	$265,539	66,444 Direct	-4.48%	Disposed	1005.8% (price as of 2026-08-21)
Oct. 19, 2011	COST	F	2,305	$84.38	$194,496	69,557 Direct	-3.21%	Disposed	1017.9% (price as of 2026-08-21)
Oct. 17, 2011	COST	F	2,169	$82.36	$178,639	71,862 Direct	-2.93%	Disposed	1045.3% (price as of 2026-08-21)
Sept. 28, 2011	COST	F	3,058	$83.79	$256,230	49,031 Direct	-5.87%	Disposed	1025.7% (price as of 2026-08-21)
April 27, 2011	COST	S	1,607	—	—	52,089 Direct	-2.99%	Disposed	(price as of 2026-08-21)
April 12, 2011	COST	F	893	$76.45	$68,270	53,696 Direct	-1.64%	Disposed	1133.8% (price as of 2026-08-21)
March 10, 2011	COST	S	8,000	—	—	54,589 Direct	-12.78%	Disposed	(price as of 2026-08-21)
Oct. 22, 2010	COST	F	1,556	$64.03	$99,631	62,589 Direct	-2.43%	Disposed	1373.1% (price as of 2026-08-21)
Oct. 22, 2010	COST	F	1,484	$64.03	$95,021	64,145 Direct	-2.26%	Disposed	1373.1% (price as of 2026-08-21)
Oct. 19, 2010	COST	F	2,206	$62.21	$137,235	65,629 Direct	-3.25%	Disposed	1416.2% (price as of 2026-08-21)
Oct. 17, 2010	COST	F	2,190	$63.70	$139,503	67,835 Direct	-3.13%	Disposed	1380.8% (price as of 2026-08-21)
Oct. 12, 2010	COST	S	7,000	—	—	70,025 Direct	-9.09%	Disposed	(price as of 2026-08-21)
Oct. 7, 2010	COST	F	3,058	$65.26	$199,565	77,025 Direct	-3.82%	Disposed	1345.4% (price as of 2026-08-21)
Oct. 7, 2010	COST	A	25,000	—	—	80,083 Direct	+45.39%	Acquired	(price as of 2026-08-21)
April 13, 2010	COST	M	15,000	$43.79	$656,850	0 Direct	-100.00%	Disposed	2054.0% (price as of 2026-08-21)
April 13, 2010	COST	S	15,000	—	—	55,083 Direct	-21.40%	Disposed	(price as of 2026-08-21)
April 13, 2010	COST	M	15,000	$43.79	$656,850	70,083 Direct	+27.23%	Acquired	2054.0% (price as of 2026-08-21)
April 12, 2010	COST	F	885	$60.35	$53,410	55,083 Direct	-1.58%	Disposed	1463.0% (price as of 2026-08-21)
Dec. 16, 2009	COST	S	5,000	$59.09	$295,450	55,968 Direct	-8.20%	Disposed	1496.3% (price as of 2026-08-21)
Nov. 16, 2009	COST	S	8,000	—	—	60,968 Direct	-11.60%	Disposed	(price as of 2026-08-21)
Oct. 22, 2009	COST	F	1,525	$58.27	$88,862	68,968 Direct	-2.16%	Disposed	1518.8% (price as of 2026-08-21)
Oct. 19, 2009	COST	F	2,279	$59.23	$134,985	70,493 Direct	-3.13%	Disposed	1492.5% (price as of 2026-08-21)
Oct. 17, 2009	COST	F	1,976	$58.48	$115,556	72,772 Direct	-2.64%	Disposed	1512.9% (price as of 2026-08-21)
Oct. 7, 2009	COST	F	2,981	$59.00	$175,879	74,748 Direct	-3.84%	Disposed	1498.7% (price as of 2026-08-21)
Oct. 7, 2009	COST	A	25,000	—	—	77,729 Direct	+47.41%	Acquired	(price as of 2026-08-21)
July 31, 2009	COST	M	15,000	$43.79	$656,850	15,000 Direct	-50.00%	Disposed	2054.0% (price as of 2026-08-21)
July 31, 2009	COST	S	15,000	—	—	52,729 Direct	-22.15%	Disposed	(price as of 2026-08-21)
July 31, 2009	COST	M	15,000	$43.79	$656,850	67,729 Direct	+28.45%	Acquired	2054.0% (price as of 2026-08-21)
April 14, 2009	COST	M	15,000	$37.35	$560,250	0 Direct	-100.00%	Disposed	2425.4% (price as of 2026-08-21)
April 14, 2009	COST	S	15,000	—	—	52,729 Direct	-22.15%	Disposed	(price as of 2026-08-21)
April 14, 2009	COST	M	15,000	$37.35	$560,250	67,729 Direct	+28.45%	Acquired	2425.4% (price as of 2026-08-21)
April 12, 2009	COST	F	861	$46.90	$40,381	52,729 Direct	-1.61%	Disposed	1911.2% (price as of 2026-08-21)
Oct. 19, 2008	COST	F	2,288	$57.98	$132,658	53,590 Direct	-4.09%	Disposed	1526.9% (price as of 2026-08-21)
Oct. 17, 2008	COST	F	2,288	$57.98	$132,658	55,878 Direct	-3.93%	Disposed	1526.9% (price as of 2026-08-21)
Oct. 17, 2008	COST	A	25,000	—	—	58,166 Direct	+75.38%	Acquired	(price as of 2026-08-21)
April 1, 2008	COST	M	15,000	$33.75	$506,250	0 Direct	-100.00%	Disposed	2694.8% (price as of 2026-08-21)
April 1, 2008	COST	M	15,000	$43.79	$656,850	30,000 Direct	-33.33%	Disposed	2054.0% (price as of 2026-08-21)

Showing latest 100 of 167 transactions

P = Open-market purchase · S = Sale · A = Grant/award · M = Option exercise · G = Gift · F = Tax withholding

Insider transactions are not a recommendation; sales are often driven by liquidity or tax reasons.

Derivative holdings (Form 4 Table II)

Options, RSUs and convertible securities reported on Form 4 Table II.

Date	Ticker	Security	Underlying	Exercise price	Expiration	Shares	A/D
April 13, 2010	COST	Stock Option	Common Stock (15,000)	$43.79	April 1, 2015	15,000	Disposed
July 31, 2009	COST	Stock Option	Common Stock (15,000)	$43.79	April 1, 2015	15,000	Disposed
April 14, 2009	COST	Stock Option	Common Stock (15,000)	$37.35	April 1, 2014	15,000	Disposed
April 1, 2008	COST	Stock Option	Common Stock (15,000)	$33.75	April 1, 2013	15,000	Disposed
April 1, 2008	COST	Stock Option	Common Stock (15,000)	$43.79	April 1, 2015	15,000	Disposed
April 1, 2008	COST	Stock Option	Common Stock (15,000)	$37.35	April 1, 2014	15,000	Disposed
June 11, 2007	COST	Stock Option	Common Stock (15,000)	$33.75	April 1, 2013	15,000	Disposed
June 11, 2007	COST	Stock Option	Common Stock (15,000)	$39.25	April 2, 2012	15,000	Disposed
June 11, 2007	COST	Stock Option	Common Stock (15,000)	$43.79	April 1, 2015	15,000	Disposed
June 11, 2007	COST	Stock Option	Common Stock (15,000)	$37.35	April 1, 2014	15,000	Disposed
Oct. 16, 2006	COST	Stock Option	Common Stock (15,000)	$34.28	April 24, 2011	15,000	Disposed
April 10, 2006	COST	Stock Option	Common Stock (15,000)	$43.79	April 1, 2015	15,000	Disposed
April 10, 2006	COST	Stock Option	Common Stock (15,000)	$37.35	April 1, 2014	15,000	Disposed
April 10, 2006	COST	Stock Option	Common Stock (15,000)	$30.41	April 1, 2013	15,000	Disposed
April 10, 2006	COST	Stock Option	Common Stock (15,000)	$38.79	April 2, 2012	15,000	Disposed
March 6, 2006	COST	Stock Option	Common Stock (15,000)	$37.35	April 1, 2014	15,000	Disposed
March 6, 2006	COST	Stock Option	Common Stock (45,000)	$38.79	April 2, 2012	45,000	Disposed
Oct. 25, 2005	COST	Stock Option	Common Stock (75,000)	$43.00	March 13, 2010	75,000	Disposed
June 16, 2005	COST	Stock Option	Common Stock (60,000)	$34.28	July 10, 2011	60,000	Disposed
June 16, 2005	COST	Stock Option	Common Stock (30,000)	$30.41	April 1, 2013	30,000	Disposed
April 1, 2005	COST	Stock Option	Common Stock (75,000)	$43.79	April 1, 2015	75,000	Acquired
Nov. 11, 2004	COST	Stock Option	Common Stock (25,000)	$36.91	Feb. 9, 2009	25,000	Disposed
Nov. 8, 2004	COST	Stock Option	Common Stock (25,000)	$36.91	Feb. 9, 2009	25,000	Disposed
Oct. 26, 2004	COST	Stock Option	Common Stock (25,000)	$36.91	Feb. 9, 2009	25,000	Disposed
Oct. 21, 2004	COST	Stock Option	Common Stock (25,000)	$36.91	Feb. 9, 2009	25,000	Disposed
April 1, 2004	COST	Stock Option	Common Stock (75,000)	$37.35	March 31, 2014	75,000	Acquired
April 1, 2004	COST	Stock Option	Common Stock (75,000)	$37.35	March 31, 2014	75,000	Acquired
March 5, 2004	COST	Stock Option	Common Stock (40,000)	$22.88	Feb. 17, 2008	40,000	Disposed

Exercise/conversion price is blank when not applicable (e.g. RSUs).

Compensation (DEF 14A)

Matched by name from proxy statements (DEF 14A) — verify against the filing.

COST

Fiscal year	Salary	Bonus	Stock awards	Option awards	Non-equity incentive	Pension change	Other	Total
2017	$688,554	$75,269	—	—	—	$29,538	$109,770	$3,845,688
2016	$657,730	$50,223	—	—	—	$21,094	$105,944	$3,776,894
2015	$642,618	$77,073	—	—	—	$12,303	$98,960	$3,625,394

Figures from the Summary Compensation Table of the company's proxy statement (DEF 14A). Compensation is not a recommendation.